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EIRP: Equivalent isotropically radiated power or Effective isotropic radiated power is the amount of power that a theoretical isotropic antenna (that evenly distributes power in all directions) would emit to produce the peak power density observed in the direction of maximum antenna gain. EIRP can take into account the losses in transmission line and connectors and includes the gain of the antenna. The EIRP is often stated in terms of decibels over a reference power emitted by an isotropic radiator with an equivalent signal strength.

11.
What is a Satellite ? <ul><li>A satellite is basically any object that revolves around a planet in a circular or elliptical path. </li></ul><ul><li>satellites were exotic, top-secret devices. They were used primarily in a military capacity , for activities such as navigation and espionage. </li></ul><ul><li>Now they are an essential part of our daily lives. We see and recognize their use in weather reports, television transmission by DIRECTV and the DISH Network, and everyday telephone calls </li></ul>

12.
How Is a Satellite Launched into an Orbit? <ul><li>All satellites today get into orbit by riding on a rocket . </li></ul>

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Orbital velocity <ul><li> Orbital velocity is the velocity needed to achieve balance between gravity's pull on the satellite and the inertia of the satellite's motion </li></ul><ul><li>-- the satellite's tendency to keep going. </li></ul>

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Whose Satellite Was the First to Orbit Earth? <ul><li>The Soviet Sputnik satellite was the first to orbit Earth, launched on Oct. 4, 1957. </li></ul>Sputnik 1, the first satellite, shown with four whip antennas

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Sputnik 2 - Mission <ul><li>Some scientists believed humans would be unable to survive the launch or the conditions of outer space, so engineers viewed flights by non-human animals as a necessary precursor to human missions. </li></ul>Laika was a Soviet space dog that became the first animal to orbit the Earth – as well as the first animal to die in orbit.

20.
Manned spacecraft <ul><li>On 12 April 1961, aboard the Vostok 1, Yuri Gagarin became both the first human to travel into space, and the first to orbit the earth. </li></ul>

21.
<ul><li>He founded the </li></ul><ul><li>Indian Space Research Organisation (ISRO). </li></ul>After Sarabhai died in 1971, the Vikram Sarabhai Space Center (VSSC) in Tiruvananthapuram is named for him. മല്ലിക സാരാഭായ് <ul><li>The Padma Bhushan is the third highest civilian award in the Republic of India, after the Bharat Ratna and the Padma Vibhushan, but comes before the Padma Shri. It is awarded by the Government of India. </li></ul>

23.
IN July 18, 1980, India launched the satellite Rohini 1 on an Satellite Launch Vehicle (SLV) rocket from the Sriharikota Island launch site

24.
Space station <ul><li>A space station (or orbital station) is a spacecraft capable of supporting a crew which is designed to remain in space (most commonly in low Earth orbit) for an extended period of time, and to which other spacecraft can dock. </li></ul>Habitability These stations have various issues that limit their long-term habitability, such as very low recycling rates, relatively high radiation levels and a lack of gravity. Some of these problems cause discomfort and long-term health effects .

25.
NB: Terms <ul><li>The path a satellite follows is an orbit . </li></ul><ul><li>In the orbit, the farthest point from Earth is the apogee , </li></ul><ul><li>and the nearest point is the perigee </li></ul>

42.
Link budget of satellites <ul><li>Parameters like attenuation or received power determined by four parameters: </li></ul><ul><li>sending power </li></ul><ul><li>gain of sending antenna </li></ul><ul><li>distance between sender and receiver </li></ul><ul><li>gain of receiving antenna </li></ul><ul><li>Problems </li></ul><ul><li>varying strength of received signal due to multipath propagation </li></ul><ul><li>interruptions due to shadowing of signal (no LOS) </li></ul><ul><li>Possible solutions </li></ul><ul><li>Link Margin to eliminate variations in signal strength </li></ul><ul><li>satellite diversity (usage of several visible satellites at the same time) helps to use less sending power </li></ul>L: Loss f: carrier frequency r: distance c: speed of light

49.
Handover in satellite systems <ul><li>Several additional situations for handover in satellite systems compared to cellular terrestrial mobile phone networks caused by the movement of the satellites </li></ul><ul><ul><li>Intra satellite handover </li></ul></ul><ul><ul><ul><li>handover from one spot beam to another </li></ul></ul></ul><ul><ul><ul><li>mobile station still in the footprint of the satellite, but in another cell </li></ul></ul></ul><ul><ul><li>Inter satellite handover </li></ul></ul><ul><ul><ul><li>handover from one satellite to another satellite </li></ul></ul></ul><ul><ul><ul><li>mobile station leaves the footprint of one satellite </li></ul></ul></ul><ul><ul><li>Gateway handover </li></ul></ul><ul><ul><ul><li>Handover from one gateway to another </li></ul></ul></ul><ul><ul><ul><li>mobile station still in the footprint of a satellite, but gateway leaves the footprint </li></ul></ul></ul><ul><ul><li>Inter system handover </li></ul></ul><ul><ul><ul><li>Handover from the satellite network to a terrestrial cellular network </li></ul></ul></ul><ul><ul><ul><li>mobile station can reach a terrestrial network again which might be cheaper, has a lower latency etc. </li></ul></ul></ul>

50.
What’s on a satellite? Communications Power Sensors/Instruments “ Bus”